Which of bronfenbrenner's five levels provides the connections between the various aspects of the person's life, like links in a chain-to bind children to parents, students to teachers, employees to bosses, and friends to friends?

The answer is "mesosystem".

The mesosystem is a segment of the ecological systems theory created by Urie Bronfenbrenner in the 1970s. It recommends that children don't grow just by impact from their nearby familial condition - encompassing situations are persuasive on the improvement of the tyke also.  

The mesosystem influences children specifically and are collaborations between two microsystems. Mesosystems can be enduring, (for example, their family's contribution in their neighboorhood consistently) or a one time just occasion (like a parent overseeing a school dance).

they protect against unsafe foods and medicines being sold

explanation:

answer; procedure;